Network Settings for Nexus One - sudden loss of data network connectivity

[Missmeamea]

I've had AT&T service with a Samsung Blackjack II for a year now. A friend recently gave me an unlocked Nexus One that was purchased directly from Google last year. I popped the SIM card in and it immediately recognized, no problems. I did notice that browsing was slow and I didn't get 3G coverage, just EDGE. However, twice now the phone just flat out loses data network. The first time, I put the SIM card back into the Blackjack and used it for a day or two, then gave the N1 a try again, and it worked just fine. This second time, I'm trying more dilligently to figure out what the problem is and am completely at a loss after speaking with both HTC and AT&T. I can make calls, I can get test text messages from AT&T, and I can access internet via wifi. HTC gave me some new settings to try, and when those didn't work, told me to call AT&T back and ask them to reprovision the phone. AT&T hasn't done that yet and says since they don't support the phone, they can't help. These are the APN settings I am using.

Name: AT&T
APN: wap.cingular
Proxy: 66.209.11.32 (have also tried blank)
Username:WAP@CINGULARGPRS.COM
Password:CINGULAR1
Server: leave blank
MMSC: http://mmsc.cingular.com
MMS Proxy: wireless.cingular.com
MMS Port: 80
MCC:310
MNC:410
APN Type: leave blank

[rugmankc]

There's a networkfix.zip out there you can try--google it, I don't have link atm

It's somewhere on this forum and XDA


Also, under Mobile Networks/Network Operators choose "Select Automatically"